Ethiopia, Gonder, Royal Enclosure.

Estonia, Tallinn, Towers in the Old Town.

Italy, Campania, Naples, Castel Nuovo, also known as Maschio Angioino.

Italy, Campania, Naples, Castel Nuovo, also known as Maschio Angioino.

France, Corsica, Calvi, The Citadel.

France, Corsica, Calvi, View of the Citadel from the harbour.

France, Corsica, Calvi, The Citadel.

England, East Sussex, Eastbourne, Redoubt Fortress and Military Museum, Royal Parade.

England, East Sussex, Eastbourne, Redoubt Fortress and Military Museum, Royal Parade.

England, East Sussex, Eastbourne, Redoubt Fortress and Military Museum, Royal Parade.

Spain, Andalucia, Cordoba, The fortified walls of the Alcazar.

Uzbekistan, Bukhara, Outer walls of the Ark Fortress, Registan Square.